This invention relates to load supporting frame assemblies and, in particular, relates to load supporting frame assemblies which have utility in flatbed road trailers, self propelled vehicles and bridge sections, of a bolted construction, which can be readily assembled and disassembled and modified for various load requirements.
Flatbed trailers for road use are generally manufactured of steel and comprise a pair of longitudinal I-beams with transverse beams passing through the longitudinal I-beams and welded together to form an integral structure. Conventional flatbed trailers are structurally massive to support heavy loads, thus reducing available payload capacity.
The assembly of an integral trailer structure by welding necessitates a relatively long assembly time and the employment of skilled workmen. Any damage to a trailer necessitates expensive repairs or scrapping of the trailer due to the difficulty and time required in removing damaged portions of the trailer and re-assembling the trailer to its operative condition.
U.S. Pat. No. 3,319,393 issued May 16, 1967 discloses a flatbed trailer construction intended to overcome some disadvantages inherent in conventional designs. For example, the trailer construction disclosed in this patents provides a flatbed structure which is sufficiently tight to prevent the loss of comminuted materials such as, for example, grain when the flatbed is provided with side walls or a hopper. However, the trailer configuration is limited to the use of longitudinally extending beams of fixed design with cross members passing through the said longitudinal members and secured thereto as by welding, thus necessitating costly fabrication techniques.
U.S. Pat. No. 3,909,059 issued Sept. 30, 1975 relates to a floor and frame construction of a load carrying vehicle preferably formed of extruded aluminum components. The main longitudinally extending beams are of a fixed cross-section precluding facile variation of beam depth according to strength requirements.